Cards and other devices for performing financial transactions may operate in online or offline modes. In an online mode, communication is established with a host computer of an issuer to ensure, for example, that sufficient funds are available for a transaction, that a card or other payment device has not been reported as lost or stolen, and so on. Online transactions have the advantage of potentially greater security, protecting the cardholder and the merchant from loss, theft, insufficient funds, and the like. However, they may be relatively slow and/or inconvenient, and may therefore be avoided by cardholders, especially for lower value transactions.
U.S. Patent Application Publication 2003-0163424 of Kumamoto discloses an electronic money transaction processing system. The system generates electronic money data which corresponds to a refund amount in response to a refund request from a user, and transmits this electronic money data directly to an IC card. Therefore, the user is able to instantly receive the refund amount as electronic money and, because the user is relieved of the task of paying electronic money from his or her own banking facility account to the IC card, user convenience is improved. An operator inputs past transaction data which is to be the subject of a refund via an input unit of an electronic money terminal and in accordance with a receipt. Then, the electronic money terminal connects to the server so as to be capable of communicating therewith (on-line) to thereby transmit a refund request which includes the inputted transaction data (input data) and the refund request amount to the server.
U.S. Pat. No. 5,055,657 of Miller et al. discloses a vending type machine dispensing a redeemable credit voucher upon payment interrupt. The machine has a computer that is connected via a data communication line with a central computer located in a central office. In order, despite the absence of an intermediate cash box for bills received during an interrupted payment process, to be able to protect against fraudulent refunds for equivalent values on vouchers issued by such machines, a plain language as well as machine-readable coded data entry is printed on the voucher, with this data entry, in addition to the value of the bill, also containing the location indication of the particular machine, and the actual date and time in seconds. This data entry is entered in a data-protected memory of the machine, and is entered via the data communication line in a data-protected memory of the central computer. Upon redemption of the voucher at the central office, the coded data entry is read and this is compared with the data stored in the memory of the central computer prior to paying out the equivalent value.
In an offline mode, a transaction can proceed without establishing communication with a remote host. Cards or other payment devices may be provided that function in an exclusively offline mode, an exclusively online mode, or in both offline and online modes. So-called “smart” cards, containing integrated circuit (IC) chips can be used for electronic payments, and may offer an “offline balance” that might be used by a cardholder to monitor available funds for offline spending. Offline spending may be convenient for low value transactions and at remote locations where connection to a remote host is not possible. One example is that of parking meters. Another is that of vending machines.
Currently, when a transaction takes place, the offline balance is reduced by the value of the transaction. However, if a mistake has been made (for example, the vend fails in a vending machine, and a refund is needed) there is currently no way to correct the offline balance of the card or other device.
Accordingly, a need exists for a way to adjust a transaction (e.g., to reverse the transaction in the case of a failed vend), which will maintain a correct offline balance (e.g., the balance is not reduced in the case where a transaction is reversed or aborted). It would also be desirable if such techniques for transaction adjustment could be developed to function in a simple yet secure fashion.